Crushing or pulverizing mill.



T. J. STURTEVANT.

ORUSHING OR PULVERIZING MILL.

APPLIOATION FILED MAY 22, 1912.

1,1 20,250. Patented Dec. 8, 1914.

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Fig.1.

511 mm for:

61 Her/H21 5,

T. J. STURTBVANT.

GRUSHING 0R PULVERIZING MILL.

APPLICATION FILED MAY22, 1912.

Patented Dec. 8, 1914.

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UNITED STATES PATENT OFFICE.

THOMAS JOSEPH STURTEVANT, '01! WELLESLEY, MASSACHUSETTS, ASSIGNOR T STURTEVANT MILL COMPANY, A CORPORATION OF MAINE.

Specification of Letters Patent.

Application filed May 22, 1912. Serial No. 699,048.

To all whom it may concern Be it known that I, THOMAS J. S'rrm'ra vAN'r, a citizen of the United States, residing at Wellesley, in the county of Norfolk and State of Massachusetts, have invented or discovered certain new and useful Improvements -in Crushing or Pulverizing Mills, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to that class of crushing or pulverizing mills employing ro tary beaters or hammers in the orm of pivotally mounted U-shaped swinging bars or bails, and the invention hasvfor 1ts object to improve the efficiency of mills of, this class.

In carrying the invention into effect the rotary heaters of the improved machine are pivotally mounted on pins which are in turn eccentrically supported by bushings loosely mounted in flanges of a rotating head, so .that said beaters will be yieldingly mounted,

' thereby affording a certain flexibility in the operation of said heaters which contributes to their eiiiciency as also to their durability, in that the strain and wear thereon is lessened. Also in the improved machine the casing thereof is formed in two parts, the lower part supporting a screen formed of grate bars and the rotary shaft which car ries the beaters, while the upper part of the casing, which carries the'breaking or impact lates, is adjustably mounted relative to the lbwer art of the casing, so that the posiol the breaking plates may bechanged somewhat relative to the rotating beaters. The feed hopper is preferably hinged to the upper portion of the casing, so that it may be opened or swgng aside, like a door, to afford convenient access to the interior of the mill, when desired, and the heaters are rotated in such a direction that incoming material will first be hurled against the breaking lates in the upper portion of the casing be ore it is carried toward the grate bars in the lower portion of the casing.

In the accompanying drawings Figure 1 is an end view of the improved machine; Fig. 2 is a transverse section thereof; Fig. 3 is a side view of the machine, and Fig. 4 is a vertical longitudinal section of the same.

,Figs. 5 and 6 are detail views of one of the loosely mounted disks or bushings.

Referring to the drawings, the casing of the machine comprises a lower or bed portion 12 provided with dust-proof boxes 13 incloslng the bearings for the driving shaft 13 provided at one end with a driving pulley l5, and at 1ts opposite end with a smaller pulley 16. The hollow bearing boxes aflord chambers to contain a lubricant for the drivmg shaft, and which lubricant is carried to said shaft by oiling rings 17. The shaft 14 is preferably provided with collars 18 which are received 1n downwardly opening chamhers or recesses 19 outside of the end ortions of the casing or bed 12, said co ars serving as stops for any dust or grit which may work outward from the chamber of the mill, so as to protect the shaft bearingsfrom such dust or grit. Said collars alsoserve to prevent 011 from the bearings in the boxes 13 from working inward to the chamber of the mill, as any oil reaching said collars is discharged therefrom by centrifugal action and escapes from the bottom of-the chambers or recesses 19.

Splined to the shaft 14 is a head 20 having flanges 21 in which are loosely mounted disks or bushings 22 socketed for the pivot pins 23 of the cranked or U-shaped beaters 24, these loosely mounted disks or bushings 22 thus affording yielding supports for the said boaters and their pivot-pins.

The upper portion 25 of the casing is adustabl attached to the lower portion thereo by suitable bolts, as 26, which pass through slotted openings in the lower part of the casing, and the position of said upper part of the casing may be varied, relative to said lower part,.and to the rotary heaters, when the said bolts are loosened, by means of shims 27, a greater or lesser number of which may be inserted between the two casing parts, as more clearly shown in Fig. 3. The said upper part of the casing is. provided with liners or breaking plates 28, 29, 30 and 31. The liners 28, against which the incoming material is first hurled, constitute the first breaker, the liner 29 the second breaker, and the liner 31 the third breaker, these several breakers being arranged at different angles relative to the radii of the circular path of travel of the heaters; so. that the material to be crushed will be hurled against them as nearly at right angles as possible, as indicatedby the arrows in Fig;

Patented Dec. 8, 1914.

2, and will thus be more efl'ectively Icrushed than would be the case if it were to strike these breakers with glancing'blows.

In the lower portion 12 of the casing is mounted a screen composed of the grate bars 32 which rest on curved supporting bars 33 the ends of which are hooked into eye-bolts 34 provided at their tops, outside of the easing, with nuts 35 which are conveniently accessible for tightening the supporting bars 33 and the grate bars resting thereon, when necessary.

The material to be crushed is fed to the machine through a hopper 36 the lower open portion of which registers with an opening 37 in the upper portion 25 of the casing, the said hopper resting on a ledge or shelf 38 alforded by the lower part of the casing. The said hopper 36 is preferably mounted on hinges 39 so that it may be opened or swung aside horizontally, like a door, to alford access to the chamber of the casing. The hopper is secured in working position by a swinging U-shaped latch 40 plvotally mounted on the casing'35, and provided with a securing screw 41 engaging a lateral projection 42 on the hopper. I

Each of the disks or bushings 22 is provided at its outer side with a locking flange 43 to prevent endwise movement of said disk or bushing and which locking flange is interrupted or cut away at one side or part. The flanges 43 are'received in annular grooves 44 formed .in the heads, 20. The said disks or bushings may be inserted in or removed from the flanges 21. of the heads 20 by turning said disks or bushings to such posltlons as to cause the cut-away parts of {their flanges to register with the small lips 47 on. the heads 20, outside of the grooves 44, as will be understood. Access to the chamber ;of the lower part 12 of the casing is affprded byside openings or hand holes each of which is closedby a removable cover 48 held in place by a locking bar 49 and set screw 50. By loosening said set screw and then partially turning said locking bar to release it from engagingprojections on the frame, the said cover will be free to be removed.

From the foregoing it will be understoodthat when the mill is in operation the incoming material will be acted on by the rotary heaters, and will be projected or hurled against, the breaking plates or breakers, and

will be reduced, not only by impact of the material against the breakers, but by direct crushing blows delivered by the rotary heaters. There is also a shearing breaking action between the lower edges of the breaking plates 29 and 31 and the peripheral edges of the U-shaped swinging heaters 24 and which peripheral edges extend parallel, or approximately so, to the said edges of said plates; and this shearing. breaking action ma am otherwise come upon them, if pivotally but otherwise unyieldingly mounted, as hereto.-

fore, on the rotating head or part by which they are carried, is greatly lessened Also by adjusting the upper portion of the casing 7 containing the breakers or breaking plates,

relative to the lower portion of the casing,

and to the path of travel of the rotating.

heaters, the second breaker 29 and the third breaker 31 may be brought into such desired relation to the hammers as will be most efflcient in the crushing or pulverizing operation, and the positions of the other breakers may also be somewhat changed. This co operative action of the U-shaped swinging.

heaters 24 and the adjustable breakers or breaking plates will be readily understood from Figs. 2 and 4 of the drawings. These parallel, or approximately so, transversely of the machine, with the inner corners or edges of the breakers or breaking plates 29 and 31 mounted on the adjustable casing part 25, so that by varying the distance between the parallel, or approximately parallel, transversely extended opposing surfaces of said heaters and cotiperating breakingplates the shearing breaking action of these parts may be rendered most efficient for the material being operated on by the proper .adjustment according to the character of such material.

The invention is not to be understdod as being limited to the details herein shown,

as the rotating beaters might be yieldingly .95. U-shaped swinging beaters have extended outer peripheral edges which are disposedsupported otherwise than by the particular loosely mounted disks or bushings herein shown and. described, without departing from the spirit of the invention.

Having thus described my invention I claim and desire to secure by Letters Patent 1.111 a crushing mill,, the combination with a rotary shaft, of a head fixed thereto and provided with flanges, socketed disks'or bushings loosely mounted in said flanges so as to be free to turn, pivotpins mounted in said socketed disks or bushings, and swinging heaters carried by said pivot pins.

2. in a crushing" mill, the combination with a rotary shaft, of ahead fixed thereto and provided with flanges, socketed disksor bushings loosely mounted in said flanges so.

" as to be free to turn, pivot pins mounted in said socketed disks or bushings, and swinging beaters carried by said pivot pins, the said heads being provided with grooves and the said soeketed disks or bushings being provided with looking flanges engaging said grooves.

3. In a crushing mill, the combination with a horizontally divided casing the upper part of which is adjustable horizontally relative to the lower portion, of breakers or breaking plates mounted on said upper adjustable casing part,.a rotary shaft mounted THOMAS JOSEPH STURTEVANT. Witnesses:

W. F. ELLIS, L. J. STURTEVANT. 

